Respiration rate (RR) and respiration volume (RV) are vital signs to be monitored in hospitalized or bedridden patients. Measurement of RR and/or RV is currently not performed at all, rather inaccurately, or in a time consuming way (e.g. by a nurse who counts inhalations of a patient over a defined period of time, then records the metric in a chart, manually). Automated methods are therefore desirable.
Known systems and methods particularly use tension belts mounted around the chest, accelerometers placed on the chest or cameras aimed at the chest equipped with video analysis algorithms. Besides the general monitoring of RR for bedridden patients, it is likely of great interest to perform detailed sleep studies.
Other modern devices, such as smart phones or cameras, also comprise a three-axis accelerometer or gyroscope for determining movements and orientation of the device, for instance to switch the display shown in the screen to the correct orientation.